[5] Volz was offered the lead singer position of REO Speedwagon in 1976 but declined due to his Christian faith.

Petra then changed sound slightly with new keyboard player John Lawry on 1984's Beat the System and reached the pinnacle of the Volz era.

They played 285 dates to 500,000 people overall on the subsequent tour and resulted in a live album, Captured in Time and Space.

[citation needed] Volz took a year off to regroup, spend time with his family and write the material that would surface on his first solo album, The River is Rising, released in 1986 on Myrrh Records.

He joined the stage with current singer, John Schlitt, for a medley of ballads, and he followed it with a solo rendition of "Grave Robber", which was one of his hits with the band.

They released an album called Back to the Rock featuring new material and re-recordings of hits from that era.

Back to the Rock II was released in 2017 and similar to its predecessor, features nine re-recorded Petra classics (plus a cover of Aerosmith's "Dream On").